Passive films formation on thermally processed industrial titanium alloys, in concentrated chloride solutions

In this paper, the passivation behaviour of the thermal treated titanium alloy Ti-1Ni-0.5Mo in concentrated chloride solutions, at high temperatures is presented. The alloying of the titanium with molybdenum and nickel has the following effects on the passivity behaviour of the industrial, ternary Ti-1Ni-0.5Mo alloy: the shifting in noble direction of the allow corrosion potentials due to the couple galvanic effect of the molybdenum and nickel: the enlargement of the alloy passive potential ranges as result of the molybdenum and nickel participation with its insoluble compounds at the Consolidation of the alloy passive film; the decrease of the alloy passive current densities because of the same consolidation effect of the passive layer; both the titanium and Ti-1Ni-0.5Mo alloy do not present pitting corrosion; the decrease of the alloy corrosion rates in concentrated chloride solutions, in comparison with the base metal, The thermal treatment by forging improved the protective properties of the passive films formed on the alloy surface.